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1.
Mouse neuroblastoma tumors have only the fifth isozyme band (A(4)) of lactate dehydrogenase, whereas this band is missing in the brain which contained four other bands of lactate dehydrogenase. The alpha-esterase isozyme patterns of tumors, kidney, and brain are similar except that there is an additional slowest-moving form of esterase in all tumor tissues. The malate dehydrogenase pattern is not altered in any of the tissues. 相似文献
2.
The amount of lactate dehydrogenase isozyme 4 in erythrocytes of mice is controlled by alleles at the Ldr-1 locus. The A subunits of lactate dehydrogenase from erythrocytes deficient in isozyme 4 cannot assemble in vitro with B subunits to form active isozyme. The inability to form hybrid enzyme is not due to a mutation in the structural gene for the A polypeptide. Rather, a factor that is bound to the A subunits of erythrocytes restricts free exchange with B subunits. 相似文献
3.
Electrophoretic resolution of lactate dehydrogenase in mature testes from a variety of animals revealed one or more unusual isozymes in addition to the usual five forms. Dissociation of the enzyme and recombination of the polypeptide subunits led to the formation of new isozymes and to a redistribution of activity among those normally present, indicating that lactate dehydrogenase synthesis in postpubertal testis is controlled by more than two genes. 相似文献
4.
A unique form of lactate dehydrogenase was observed in the starch-gel electrophoretic patterns of adult human testes. It was present in sperm, but absent in prepubertal testes. Its electrophoretic mobility, heat stability, kinetic behavior with pyridine nucleotide analogs, and chromatographic characteristics on diethylaminoethyl cellulose were intermediate to those observed for lactate dehydrogenase isozymes 3 and 4. 相似文献
5.
Homology of lactate dehydrogenase genes: E gene function in the teleost nervous system 总被引：4，自引：0，他引：4
G S Whitt 《Science (New York, N.Y.)》1969,166(909):1156-1158
Data obtained from immunochemical studies and the use of allelic variants support the hypothesis that the lactate dehydrogenase isozymes unique to the teleost nervous system are encoded in a third locus. Immunochemical and other studies demonstrate that this third locus is closely related to the lactate dehydrogenase B locus. 相似文献
6.
Heterozygosity occurs at the lactate dehydrogenase b-locus in two diploid parthenogenetic species of Cnemidophorus. Each such species produces two different B subunits, one of which is also found in two sexual species and in two triploid parthenogenetic species; the other occurs also in a third sexual species. Interspecific hybridization between sexual species carrying different b-alleles and producing different B subunits may be responsible for the heterozygosity at the lactate dehydrogenase b-locus in diploid parthenogenetic Cnemidophours. 相似文献
7.
The isozyme patterns of lactate dehydrogenases of various tissues were studied on 51 hagfish by starch-gel electrophoresis. Nine lactate dehydrogenase phenotypes were encountered, suggesting the coexistence of two alleles at each of the two separate gene loci. There apparently was no interaction between the products of these two separate loci. Even the products of two alleles at the same locus were apparently incapable of forming hybrid molecules, an indication of the possible monomeric nature of each lactate dehydrogenase molecule. 相似文献
8.
半番鸭网床平养与地面平养对比试验 总被引：1，自引：0，他引：1
为探讨半番鸭网床饲养效果,将大型白羽半番鸭采用网床平养与地面平养2种饲养方式进行对比试验,分析其生产性能、屠宰性能、肌肉品质、血清生化指标和经济效益。结果表明：网床平养组平均每只净增重比地面平养组多119.87 g（3.90%）（P〈0.05）,2种养殖模式对半番鸭饲料报酬、成活率、屠宰性能和肌肉品质的影响没有显著差异（P〉0.05）;血清生化指标中,白蛋白、直接胆红素、肌酸激酶、二氧化碳和载脂蛋白B 2组间差异显著（P〈0.05）,血糖、门冬氨酸氨基转移酶、CK同工酶、乳酸脱氢酶、羟丁酸脱氢酶和钠2组间差异极显著（P〈0.01）。综上,网床平养半番鸭的饲养效益优于地面平养。 相似文献
9.
Triploid parthenogenetic lizards which are heterozygous at the lactate dehydrogenase b locus show approximately two doses of the b allele and approximately one dose of the b' allele. This finding agrees with the triploid karyotype composed of two haploid complements of chromosomes indistinguishable from those of species carrying the b allele and one complement indistinguishable from that of the species which carries the b' allele. Densitometry of electrophoretic patterns of lactate dehydrogenase from heart muscle and from kidney indicates approximately equal expression of each of the b alleles in the triploid lizards. Heterozygouis diploid lizards from the same parthenogenetic species, in agreement with their karyotype, show equal doses of b and b' alleles. 相似文献
10.
尖孢镰刀菌异核体及其不同核型分离子的孢子萌发时期同工酶分析 总被引：4，自引：0，他引：4
在获得尖孢镰刀菌棉花萎蔫专化型异核体菌株及其3个稳定的不同核型分离子的基础上，选择孢子萌发时期的幼嫩菌丝制备粗酶提取液，采用聚丙烯酰胺凝胶电泳方法进行了7种同工酶分析。结果表明，酯酶和乳酸脱氢酶电泳图谱在4个样品中完全一致；没有致病能力的菌株在葡萄糖－6磷酸脱氢酶在苹果酸脱氢酶的表达量高于致病力强的菌株；致病力强的菌株没有乙醇脱氢酶的表达。在4个样品中都没有检测到苹果酸酶和过氧化氢酶。 相似文献
11.
A specific, highly active malate dehydrogenase by redesign of a lactate dehydrogenase framework 总被引：19，自引：0，他引：19
H M Wilks K W Hart R Feeney C R Dunn H Muirhead W N Chia D A Barstow T Atkinson A R Clarke J J Holbrook 《Science (New York, N.Y.)》1988,242(4885):1541-1544
Three variations to the structure of the nicotinamide adenine dinucleotide (NAD)-dependent L-lactate dehydrogenase from Bacillus stearothermophilus were made to try to change the substrate specificity from lactate to malate: Asp197----Asn, Thr246----Gly, and Gln102----Arg). Each modification shifts the specificity from lactate to malate, although only the last (Gln102----Arg) provides an effective and highly specific catalyst for the new substrate. This synthetic enzyme has a ratio of catalytic rate (kcat) to Michaelis constant (Km) for oxaloacetate of 4.2 x 10(6)M-1 s-1, equal to that of native lactate dehydrogenase for its natural substrate, pyruvate, and a maximum velocity (250 s-1), which is double that reported for a natural malate dehydrogenase from B. stearothermophilus. 相似文献
12.
In a group of 21 gelada baboons, three different lactate dehydrogenase patterns were observed after starch-gel electrophoresis of tissue extracts. The patterns indicate that a mutation has occurred in this population in the gene responsible for the A-subunit. The normal and variant homozygotes each contain five isozymes, those containing the A subunit having characteristically different electrophoretic mobilities. The heterozygote contains the expected 15 isozymes. 相似文献
13.
橄榄蛏蚌不同组织乳酸脱氢酶(LDH)和苹果酸脱氢酶(MDH)同工酶的电泳分析 总被引：1，自引：0，他引：1
为了解橄榄蛏蚌的生化遗传特性,采用聚丙烯酰胺凝胶垂直平板电泳,研究了橄榄蛏蚌闭壳肌、斧足、鳃、肠道、外套膜中乳酸脱氢酶（LDH）和苹果酸脱氢酶（MDH）同工酶的电泳酶谱和活性。结果表明,橄榄蛏蚌5种组织乳酸脱氢酶共检测到5条酶带,5种同工酶在闭壳肌中均有表达,在肠道和鳃中只检测到2种,在外套膜中检测到1条酶带;苹果酸脱氢酶检测到4条酶带,其中闭壳肌含有4条谱带,鳃、斧足和盲肠具有3条谱带,而外套膜具有2条染色很浅的微弱带。可见2种同工酶的分布均具有组织特异性。 相似文献
14.
河曲马睾丸组织成纤维细胞系的建立及生物学特性研究 总被引：1，自引：0，他引：1
采集河曲马睾丸组织,用热消化法制备原代细胞,通过差速消化和差速贴壁法纯化细胞,扩大培养至第3代用液氮保存,细胞复苏后进行活力、形态、生长曲线、微生物污染、核型、乳酸脱氢同工酶谱及荧光蛋白质粒转染表达等特性研究。结果显示,河曲马睾丸组织原代和传代细胞呈成纤维型,生长良好,最大增殖数量为4.32×105 mL-1,倍增时间为34.58h;细菌、真菌、病毒、支原体检测呈阴性;染色体2 N=64,二倍体为85%,占主体;乳酸脱氢酶同工酶电泳图谱有明显特征,共有4条谱带,其中LDH3浓度较高,活性较强;外源质粒在该细胞中能进行复制和表达。表明已成功建立河曲马睾丸组织成纤维细胞系,使河曲马这一重要种质资源在细胞水平上得以保存。 相似文献
15.
Molecular size of hagfish muscle lactate dehydrogenase 总被引：2，自引：0，他引：2
In contrast to an earlier report, we find that the primitive vertebrate Eptatretus possesses a muscle lactate dehydrogenase whose molecular size is like that of lactate dehydrogenases from higher vertebrates. The molecular size of lactate dehydrogenase appears to have remained constant during evolution. 相似文献
16.
Glucose-6-phosphate dehydrogenase mosaicism: utilization as a cell marker in the study of leiomyomas 总被引：33，自引：0，他引：33
The sex-linked electrophoretic variants A and B of glucose-6-phosphate dehydrogenase were studied in 86 samples of myometrium and 27 leiomyomas from five heterozygous women. All but one sample of myometrium had both A and B bands in equal or nearly equal amounts. In contrast to this, all of the leiomyomas had either an A band or a B band. Both A and B tumors were found in all uteri. These findings are consistent with the hypothesis that these tumors arose from single cells. 相似文献
17.
P J Fritz 《Science (New York, N.Y.)》1967,156(771):82-83
The ability of lactate dehydrogenase isozyme five from rabbit skeletal muscle to catalyze pyruvate reduction is extremely sensitive to changes of pH within the range of 6.2 to 7.8.The activity of lactate dehydrogenase isozyme one from rabbit heart is virtually unaffected by changes of pH within the same range. Isozyme five is activated by low concentrations of oxalacetate and inhibited by higher concentrations, but other substrates of the citric acid cycle have no effect. 相似文献
18.
C R Shaw 《Science (New York, N.Y.)》1966,153(739):1013-1015
Two forms of glucose-6-phosphate dehydrogenase, A and B, have been reported in deer mouse tis sues. The B enzyme, which showed autosomally controlled polymorphism, is now found to be equally active to ward glucose-6-phosphate and galac tQse-6- phosphate; the A enzyme is specific for the former. Human and horse livers also have two forms of glucose-6-phosphate dehydrogenase which exhibit the same substrate spe cifities as those in the deer mouse. A wide variety of electrophoretic patterns was seen in the human galactose-active enzyme. 相似文献
19.
Mammalian oocytes: X chromosome activity 总被引：7，自引：0，他引：7
C J Epstein 《Science (New York, N.Y.)》1969,163(871):1078-1079
The glucose-6-phosphate dehydrogenase and lactate dehydrogenase contents of oocytes from XO and XX female mice have been measured. The activity of the former in the oocytes of XO mice is half of that in the oocytes of XX mice, whereas the lactate dehydrogenase activities in the two groups of ova are the same. These results indicate that glucose-6-phosphate dehydrogenase from a mouse oocyte is an X-linked enzyme, that its synthesis occurs in the oocyte and is dosage dependent, and that inactivation of the X chromosome does not occur in the mouse oocyte. 相似文献
20.
兴淮鲫(白鲫■×散鳞镜鲤■)及其双亲同工酶的研究 总被引：2，自引：0，他引：2
本文以兴淮鲫(白鲫■×散鳞镜锂■)及其双亲为材料,采用聚丙烯酰胺凝胶平板电泳法,研究了3种鱼的晶体、脑、肌肉、心脏、肝脏及肾脏等6种组织器官的乳酸脱氢酶(LDH)、苹果酸脱氢酶(MDH)、酯酶(EST)和超氧物歧化酶(SOD)等4种同工酶酶谱表达上的异同点及遗传倾向。结果表明,兴淮鲫的LDH同工酶有偏父的表达倾向;它的s-MDH和EST2种同工酶则表现出偏母表达的倾向;在SOD同工酶的表达上,与双亲相比,既有相似处,也有不同点。同时,3种鱼的4种同工酶并显现出不同程度的组织特异性。此外,在兴淮鲫的4种同工酶酶带中出现双亲没有的“新杂种酶带”及双亲的“互补酶带”,且F_1代的有些酶带的活性比双亲相应酶带的活性有所增强。 相似文献